Reuse images already loaded in the current document more aggressively

Source/core/fetch/ResourceFetcher.cpp

Index: Source/core/fetch/ResourceFetcher.cpp
diff --git a/Source/core/fetch/ResourceFetcher.cpp b/Source/core/fetch/ResourceFetcher.cpp
index 7df5fd157395b48b3b5fe739197e389275547e59..a5207ec197048ef824733c296ce550e812535749 100644
--- a/Source/core/fetch/ResourceFetcher.cpp
+++ b/Source/core/fetch/ResourceFetcher.cpp
@@ -572,6 +572,11 @@ ResourceFetcher::RevalidationPolicy ResourceFetcher::determineRevalidationPolicy
     if (existingResource->isPreloaded())
         return Use;
 
+    // List of available images logic allows images to be re-used without cache validation. We restrict this only to images
+    // from memory cache which are the same as the version in the current document.
+    if (type == Resource::Image && existingResource == cachedResource(request.url()))

[Nate Chapin, 2015/08/14 23:33:39]

Moved here to make it equivalent to preloading. I'm reasonably confident it's OK
to make this check higher priority than all of the things it now precedes.

+        return Use;
+
     // Defer to the browser process cache for Vary header handling.
     if (existingResource->hasVaryHeader())
         return Reload;
@@ -632,11 +637,6 @@ ResourceFetcher::RevalidationPolicy ResourceFetcher::determineRevalidationPolicy
         return Reload;
     }
 
-    // List of available images logic allows images to be re-used without cache validation. We restrict this only to images
-    // from memory cache which are the same as the version in the current document.
-    if (type == Resource::Image && existingResource == cachedResource(request.url()))
-        return Use;
-
     // If any of the redirects in the chain to loading the resource were not cacheable, we cannot reuse our cached resource.
     if (!existingResource->canReuseRedirectChain()) {
         WTF_LOG(ResourceLoading, "ResourceFetcher::determineRevalidationPolicy reloading due to an uncacheable redirect");